This invention relates to a medicinal means for treatment and metaphylaxis of urate, urate-oxalate and urate-phosphate lithiasis. Nephrolithiasis is a very common urological disease characterized by the presence of renal calculi, small hard concretions of urate, oxalate, cysteine, and phosphate deposits which accumulate in the kidney. Nephrolithiasis is most often treated by surgical intervention. Pharmaceutical litholysis, the nonsurgical and medicinal dissolution of calculi, is known, but these methods are generally slow and of limited reliability for wide spread therapeutic use.
Urate and mixed urate lithiasis has been treated in the past with preparations containing various salts, such as sodium and potassium citrates, bicarbonates, and citric acids. Preparation of this type include those known by the trade names Magurlite.RTM., Solurane.RTM. and another composition, Uralite.RTM., which contains certain medicinal plant extracts useful for litholysis. All of these compositions rely on the ability of the salts or extracts to maintain a pH of 7 in the urine, thus hampering the crystallization of uric acid in patients prone to renal lithogenesis.
The Magurlite.RTM. preparation is a Hungarian preparation. Its composition is as follows:
Pyridoxine hydrochloride 0.008 PA2 Magnesium citrate 0.18 PA2 Sodium citrate 0.723 PA2 Potassium citrate 0.794 PA2 Citric acid 0.27. PA2 Potassium bicarbonate 35.6 PA2 Sodium citrate 30.6 PA2 Citric acid sic.. 33.7 PA2 Corrigent to 100. PA2 Sodium citrate 35.0 PA2 Potassium bicarbonate 36.7 PA2 Citric acid 33.2 PA2 Corrigent to 100.
It is provided in the form of granules in 2 grs. bag and is applied in cases of urate lithiasis. It acts also in cases of renal calculi containing oxalates. The mechanism of action lies in alkalizing the urine. It is not applied in cases of infected forms of lithiasis and circulation disturbances.
The Solurane.RTM. preparation is a Bulgarian preparation. It has the following composition:
The preparation is applied in cases of urate lithiasis. It is not applied in infected forms and mixed forms of the disease. The mechanism of action lies in alkalizing the urine up to pH-7.
The Uralyte.RTM. preparation is a West German preparation.
Its composition is the following:
Its mechanism of action also lies in alkalizing the urine. It is applied in cases of urate lithiasis. The preparation has no application in cases of infected forms of the disease.
All these known preparations' act by dissolving the concrements by means of alkalizing the urine and dissolving the uric acid. The action according to the present invention is different:
(a) reducing the surface urine tension in cases of lithiasis where said tension is higher than in the urine of healthy people; PA1 (b) forming with the uric acid (from the concrements) a water-soluble complex composition without changing the reaction of urine.
The "active ingredient" of the inventive means is not a "basic ingredient" in the sense of one with a basic chemical character. On the contrary, it is provided by a neutral chemical reaction. The active ingredient is a mixture of 2/3 monoester and 1/3 diester of polyetheleneglycol with higher unsaturated fatty acids having a molecular weight of about 1000.
The known preparation suffer from a number of disadvantages. First, it is difficult to accurately maintain the physiological pH at the desired therapeutic level throughout administration of the preparations. The pH may increase beyond 7, allowing phosphate precipitation in the alkaline urine. Thus, the kidney infection may proceed despite administration of the known preparations. Second, the known compositions work very slowly. They require clinical administration over a period of several months before any therapeutic result is evident. Third, the known compounds are toxic, and patients often suffer from side-effects during the long course of treatment. Fourth, the known compounds are not suitable for infectious or mixed urate forms of lithiasis.